The effect of nasal structure on olfactory function in patients with OSA

Area of Science:

• Otorhinolaryngology
• Sleep Medicine
• Neuroscience

Background:

• Obstructive sleep apnea (OSA) is a condition affecting breathing during sleep.
• Olfactory dysfunction can be a symptom in patients with OSA.
• The relationship between nasal anatomy and smell in OSA patients requires further investigation.

Purpose of the Study:

• To examine the correlation between nasal structural parameters and olfactory function in adults with OSA.
• To test the hypothesis that nasal anatomy influences objectively measured olfactory performance in OSA.

Main Methods:

• Seventy-six adult OSA patients underwent polysomnography for diagnosis.
• Nasal structure was assessed using acoustic rhinometry.
• Olfactory function was evaluated using the Sniffin' Sticks (SS) smell test, measuring olfactory threshold (OT), discrimination (OD), and identification (OI).

Main Results:

• Minimum cross-sectional area (MCA) of the nose showed a significant positive correlation with the SS composite score (r=0.434, p<0.001), driven by OT and OD.
• Nasal volume (NV) was also associated with the SS composite score (r=0.350, p=0.002), primarily linked to OT.
• Olfactory identification (OI) did not correlate significantly with nasal structural parameters.

Conclusions:

• Nasal structure, specifically MCA and NV, significantly influences olfactory function in OSA patients.
• Altered nasal airflow due to anatomical abnormalities in OSA likely contributes to olfactory dysfunction.
• Surgical interventions targeting nasal volume and MCA may offer potential improvements in olfactory performance for OSA patients.